Bambusa Therapeutics Presents Positive Preliminary Multiple Ascending Dose Phase 1 Data for BBT002 at the European Academy of Allergy & Clinical Immunology (EAACI) Annual Congress 2026

- BBT002 is a next-generation, long-acting bispecific antibody targeting two clinically and commercially validated targets, IL-4Rα and IL-5 -

- BBT002 demonstrated rapid, deep, and sustained biomarker effects through at least 8 weeks following multiple doses, consistent with the SAD data, with a ~29.4-day half-life supporting extended dosing intervals -

- Topline data from ongoing proof-of-concept trials evaluating BBT002 in patients with COPD and CRSwNP anticipated by year-end 2026 and first half of 2027, respectively -

BOSTON, June 15, 2026 /PRNewswire/ -- Bambusa Therapeutics, Inc. (Bambusa Therapeutics), a clinical-stage biotechnology company advancing next-generation, long-acting bispecific antibodies for immunology and inflammation, today announced positive preliminary data from the multiple ascending dose (MAD) cohorts of its Phase 1 trial evaluating BBT002 in healthy volunteers. The results were reviewed in an oral presentation at the European Academy of Allergy & Clinical Immunology (EAACI) Annual Congress 2026, taking place from June 12-15, 2026 in Istanbul, Turkey.

"We are highly encouraged by the preliminary Phase 1 multiple ascending dose data of BBT002 and were pleased to present these results at the EAACI Annual Congress—one of the leading global gatherings of allergy and immunology professionals," said Thang Ho, Ph.D., Chief Development Officer at Bambusa Therapeutics. "Building on the SAD data we recently shared, the Phase 1 MAD data further support BBT002 as a potentially differentiated, long-acting bispecific antibody targeting IL-4Rα and IL-5 to address multiple complementary drivers of Type 2 inflammation. BBT002 continues to demonstrate rapid, deep, and sustained biologic activity across multiple clinically relevant biomarkers, including eosinophils, TARC, and pSTAT6, while also supporting the potential for extended dosing intervals through prolonged half-life. We believe these findings reinforce the opportunity for BBT002 to deliver more comprehensive disease control and enhanced dosing convenience for patients with respiratory and other eosinophil-driven inflammatory diseases."

The presentation titled "Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of BBT002, a Novel Bispecific IL-4Rα/IL-5 Antibody: Results from the Single- and Multiple-Ascending Dose Portions of a Phase 1 Study of Healthy Volunteers" highlighted the following data:

Percent Change in Eosinophil (EOS) Levels: EOS is a clinically established biomarker of Type 2 airway inflammation and IL-5 pathway activity, with elevated levels associated with disease severity and exacerbation risk across multiple respiratory diseases.

• BBT002 demonstrated rapid, robust, and sustained depletion of EOS for more than 8 weeks following multiple doses compared to baseline.

Percent Change in Thymus and Activation-Regulated Chemokine (TARC): TARC is a key Type 2 inflammatory chemokine that is associated with Th2-driven immune responses and is strongly correlated with disease activity across multiple respiratory inflammatory diseases.

• BBT002 demonstrated dose-dependent, rapid, deep, and sustained reduction in TARC levels following multiple doses compared to baseline.

Percent Change in Phosphorylated STAT6 (pSTAT6): pSTAT6 is a key downstream mediator of Type 2 inflammation in respiratory inflammatory disease when assessing IL-4Rα pathway activity.

• BBT002 achieved rapid, complete, and sustained inhibition of pSTAT6 for more than 8 weeks following multiple doses compared to baseline.

Pharmacokinetics (PK): BBT002 exhibited prolonged PK with a half-life of approximately 29.4 days at or above target exposure, consistent with the PK profile observed in the single ascending dose (SAD) cohorts, supporting the potential for extended dosing intervals.

Safety and Tolerability: BBT002 was observed to be well-tolerated across all doses evaluated in the SAD (previously presented at ATS 2026) and MAD cohorts throughout the trial.

Immunogenicity: The incidence and titer of anti-drug antibodies (ADA) was low, with no apparent impact on safety or PK.

"The growing body of clinical data emerging across our pipeline continues to support Bambusa's strategy of developing next-generation bispecific antibodies designed to address multiple drivers of inflammation within a single molecule," said Shanshan Xu, M.D., Ph.D., Founder & Chief Executive Officer of Bambusa Therapeutics. "As we advance BBT002 in ongoing clinical studies in patients with COPD and CRSwNP, we remain focused on evaluating its potential to deliver differentiated clinical benefit across Type 2 inflammatory diseases. In parallel, we look forward to reporting topline data this summer from our ongoing BBT001 study in atopic dermatitis. We believe these data have the potential to establish proof-of-concept for BBT001 and further inform the clinical potential of dual IL-4Rα and IL-31 inhibition in patients with atopic dermatitis."

In parallel to the Phase 1 SAD and MAD cohorts in healthy volunteers, BBT002 is being evaluated in ongoing proof-of-concept trials in patients with chronic obstructive pulmonary disease (COPD) and chronic rhinosinusitis with nasal polyps (CRSwNP), with topline results anticipated by year-end 2026 and the first half of 2027, respectively.

The BBT002 Phase 1 healthy volunteer data presentation from EAACI 2026 is available in the "Publications" section on Bambusa's website, www.bambusatx.com.

About the BBT002 Phase 1 SAD/MAD Healthy Volunteer Study Cohorts

Bambusa Therapeutics' single- and multiple-ascending-dose Phase 1 clinical trial in healthy volunteers is a randomized, blinded, placebo-controlled trial designed to evaluate the safety, tolerability, pharmacokinetics, immunogenicity, and pharmacodynamic profile of BBT002.

About BBT002

Bambusa Therapeutics' second clinical program, BBT002, is a first-in-class, multi-targeting, half-life extended bispecific antibody engineered to inhibit both IL-4Rα and IL-5 signaling. Designed as a platform-in-a-molecule, BBT002 simultaneously targets the IL-4/IL-13 pathway through IL-4Rα and the IL-5/eosinophil axis within a single therapy. We believe this differentiated approach has the potential to address multiple respiratory and other Type 2 inflammatory diseases, improve clinical outcomes, and provide greater dosing convenience through extended maintenance dosing intervals.

About Bambusa Therapeutics

Bambusa Therapeutics is a clinical-stage biotechnology company developing a portfolio of next-generation, multi-targeting medicines designed to transform patient care across chronic immunology and inflammation (I&I) diseases. The Company's bispecific antibody platform combines advanced protein engineering with half-life extension technology and high-concentration subcutaneous delivery to improve durability, convenience, and clinical differentiation. Bambusa's vision is to deliver transformative medicines for patients across every stage of life and help define the next era of I&I therapies.

• BBT001 is a first-in-class, half-life-extended bispecific antibody targeting IL-4Rα and IL-31 with best-in-disease potential. It is currently in Phase 1 proof-of-concept development for atopic dermatitis (AD) and chronic spontaneous urticaria (CSU).
• BBT002 is a first-in-class, half-life-extended bispecific antibody targeting IL-4Rα and IL-5 with platform-in-a-molecule potential. It is currently in proof-of-concept development for Type 2 inflammatory disorders including COPD and CRSwNP.
• BBT003 and BBT004 are preclinical programs focused on gastroenterology and autoimmune diseases, respectively.

For more information, please visit www.bambusatx.com. Follow Bambusa on LinkedIn.

SOURCE Bambusa Therapeutics, Inc.